Who’s been the biggest loser in the baseball playoffs, the Chicago Cubs or the Boston Red Sox? How about NBC and CBS? Fox’s baseball playoff coverage has been so popular that the rival networks have found themselves scrapping their first-run primetime shows at the last minute, rather than run them against pennant-race games.

”We’re all running into the buzz saw of baseball,” CBS spokesman Chris Ender told the Associated Press. ”For all the talk of the Cubs and Red Sox being cursed, the broadcast networks are being cursed. This is clearly wreaking havoc with the rollout of our new season.”

On Wednesday, NBC decided to pull that night’s new episodes of ”The West Wing” and ”Law & Order” and replace them with reruns, rather than waste the new shows on a night when viewers were riveted to the deciding game of the Cubs-Marlins series. On Thursday, the night of the last game of the Red Sox-New York Yankees series, the network made a similar decision, yanking its entire evening of new episodes of ”Friends,” ”Scrubs,” ”Will & Grace,” and ”ER.” (NBC had already decided to pull the struggling ”Coupling” in favor of a rerun of ”Whoopi.”) The same night, CBS pulled new episodes of ”CSI: Crime Scene Investigation” and ”Without a Trace,” though it did air a new installment of ”Survivor: Pearl Islands.”

Unlike last year, when Fox’s baseball season coverage ended with an all-West Coast World Series between Anaheim and San Francisco that drew all-time low ratings, baseball been berry berry good to Fox this year. Wednesday’s Cubs-Marlins finale drew a whopping 26.5 million viewers, according to Nielsen, making it the most-watched baseball playoff game in 10 years. Overall, the playoffs have averaged 15.9 million viewers, up 59 percent from last year.